1. Field of the Invention
This invention relates to blood anticoagulants and, more particularly, to a blood anticoagulant suitable for preventing coagulation of blood collected for purposes of hematological examination.
2. Description of the Prior Art
With the progress of clinical medicine, hematological examination has recently come to play a very important role in the field of preventive medicine or in the judgement of therapeutic effects. Under these circumstances, the development of blood anticoagulants which can prevent coagulation of blood collected for purposes of hematological examination is being actively pursued.
Blood anticoagulants comprising heparin sodium are most widely known. For example, in medical treatments using an artificial kidney or a blood oxygenator, they are added to the blood and/or used for the treatment for equipment surfaces which are in contact with the blood.
Moreover, blood anticoagulants comprising a metallic salt of ethylenediaminetetraacetic acid are being used in certain morphological tests of blood.
These blood anticoagulants are also being used in coating the internal surfaces of hematocrit tubes for the determination of hematocrit which is an item of hematological examination, and as additives for the separation of blood plasma.
However, since heparin is obtained solely by extraction from animal organs, it cannot be produced as abundantly as synthetic products and its production cost is far higher. Moreover, heparin preparations having identical structures and properties are almost impossible to obtain by extraction from different types of organs.
On the other hand, blood anticoagulants comprising a metallic salt of ethylenediaminetetraacetic acid can be used in morphological tests of blood. However, they are disadvantageous in that they do not allow inorganic ion determinations which are among biochemical tests and they exert an adverse effect on enzyme tests. For these reasons, conventional blood tests have unavoidably involved complicated procedures, i.e., the selection of different blood anticoagulants according to the intended test item and the adoption of the serum separation method in which steps must be taken to separate serum from blood prior to measurement.
Accordingly, there is a demand for a blood anticoagulant which is inexpensive, has excellent anticoagulant properties, and exerts no adverse effect on a wide variety of blood tests. However, no blood anticoagulant meeting this demand has been developed as yet.